The shimenawa is a rope of twisted rice straw that marks off sacred space, hung to signify the boundary between the ordinary and the pure and to indicate the presence of a kami.
Marking the boundary
The rope is hung across the entrance to a shrine, around a sacred tree or rock, over a doorway, or around an object or place held to be pure or inhabited by a kami, and it declares that what lies within its bound is set apart from the ordinary world. It thus functions as a visible line between the profane and the sacred, a boundary that the eye can read, and passing within it is entering consecrated ground. The twisting of the rice straw, and its scale, from a thin cord to the massive ropes of some great shrines, mark the importance of what it encloses.
Straw, streamers and the sun
From the shimenawa hang the zigzag paper streamers, the shide, whose lightning-like form completes the sign, and the two together are among the most recognisable marks of Shinto. The rope is bound up with the central myth of the sun goddess: in the account of her withdrawal into a cave, when she is drawn out a rope is stretched behind her to prevent her return to the darkness, an origin story that ties the shimenawa to the marking and securing of the sacred at the heart of the tradition. Whether around a shrine gate or a wayside rock or a rice field, the straw rope performs the same work, declaring that the space it bounds belongs to the kami.